We report the clinical course and pathologic findings in a case of intraocular sclerosing inflammatory pseudotumor in a 21-year-old man. The patient initially had a unilateral right interstitial keratitis, scleritis, uveitis, ciliary body mass, and retinal detachment. Scleral and vitreous biopsy specimens revealed an inflammatory process. The eye was eventually enucleated despite therapy with high doses of prednisone and ciprofloxacin hydrochloride. Histologic examination of the globe showed nongranulomatous, acute (neutrophils) and chronic (lymphocytes and histiocytes) inflammation with proliferation of fibrous tissue within the vitreous cavity, uvea, sclera, and contiguous orbital fibroadipose tissue. The contralateral eye later developed a similar mass that resolved following aggressive and prolonged immunosuppressive therapy with retention of 20/16 visual acuity.